With the increasing expense and weight of power and unpowered hand tools, there came recognition of the penalty associated with dropping such a tool. Power hand tools are often damaged when they are dropped, and falling hand and power hand tools can injure persons and property if dropped from an elevated position.
As a result of these circumstances, attachment devices have been devised to secure hand tools from such a drop. Some tools are manufactured with captive holes to allow the connection of a safety line. Further, lanyards and D-rings have been built into many hand power tools to allow attachment of lines to the tool at one end and a user's body at the other. For example, see U.S. Pat. No. 6,487,756 to Vidal.
Many power and unpowered hand tools, however, have no such means to attach a safety line. As a result various methods have been devised to add a safety line or lanyard to a tool that was not originally so configured.
One method is to tape a safety strap to the handle of such a tool. Python Safety, Inc. makes such a tape called Quickwrap Tape™ for this purpose. Another method is used by Tool Safety Solutions LTD, and involves placing heat sensitive tape over a section of a safety strap located adjacent the tool handle, and then apply heat to the tape allowing it to shrink and hold the section of strap in place.
A disadvantage of the tape method is that tape can lose its adhesive properties over time. Such loss of adhesion can be accelerated under use in harsh environmental conditions. The degradation of the adhesive property of tape may not be readily apparent, creating uncertainty when the tool safety strap connection might fail. This creates a safety hazard, especially when using tape to secure heavier tools that are especially dangerous when dropped.
The heat shrink method has disadvantages as well. The heating step might cause heat related damaged to the tool handle and/or the safety strap. If the heat shrink sleeve is over heated, the safety strap, or the heat shrink material itself, might well be weakened by the heating process and such a problem might go undetected. An unexpected failure of the safety strap might then occur. Further, the heating step can release undesirable toxic combustion products. In addition, heat shrink sleeves require use of a thin walled material which is required for optimum rate of heat conduction and process safety of the heat shrink sleeve. Such a thin-walled product may not be durable enough to withstand the weight of a heavy tool, especially under the stress of a dropped tool that is restrained by a safety strap held in place only by the heat shrink sleeve. The thin walled heat shrink material may also not withstand harsh environmental conditions.
Therefore, there is an unfulfilled need for a better and safer way of attaching a safety strap to a hand tool that does not possess a captive hole or built in safety strap.